CSF2 and myeloid sarcoma: Findings indicating that GM-CSF has the key role in the encephalitogenic potential of Th17 cells in mice (74, 170, 171), specifically, increased levels of GM-CSF in the cerebrospinal fluid and serum of active MS patients with the relapsing-remitting type of the disease and increased secretion of GM-CSF from T cells isolated from the peripheral blood and brain lesion of MS, suggest that GM-CSF also plays an important role in MS development (172, 173).